Electric switch



(No Model.)

s. HILL. ELECTRIC SWITCH.

' Patenhed Apr. 24, 1894.

UNITED v STATES PATENT OFFICE.

WARREN S. HILL, OF HYDE PARK, MASSACHUSETTS.

ELECTRIC SWITCH.

SPECIFICATION formingpart of Letters Patent No. 518,813, dated April24,189;

Application filed October 31, 1893.

To all whom it may concern.-

Be it known that I, WARREN S. HILL, 5f

Hyde Park, county of- Norfolk, and Commonwealth of Massachusetts, haveinvented certain new and useful Improvements in Electric Switches; and Ido hereby declare that the following is a full, clear, and exactdescription. of the invention, which will enable others skilled in theart to which it appertains to make and use the same.

One object of my invention is to produce an electric switch boardconstruction in which the fitting of the contacting parts, by which thecircuit is completed, is made accurate, and a further object is toincrease its carrying capacity.

My invention consists of certainnovel features, combinations andarrangements hereinafter described and particularly pointed out in theclaims.

In the accompanying drawings, Figure '1 is a perspective view of theelectric switch board construction. Fig. 2 is a detail perspective viewshowing one of the contact pieces and one of the blades in position tocomplete the circuit. Fig. 3 is a detail view in end elevation showingmy improved construction of the contact pieces. Fig. 4 is a detail viewshow ing the construction of the yoke connecting the two blades of theswitches. I

Like letters of reference refer to like parts throughout the severalviews.

A represents a switch board of the usual construction, and upon it are.secured the standards B and the contact pieces 0. The two blades D areindependently pivoted to the standards B by pivots E, and each blade hasat its outer end a broad end F. These two-blades are joined together attheir broad ends by a connecting yoke G of the construction shown inFig. 4, the extremities G of the yoke conforming in shape to thebroadened ends F of the blades, between which and the yoke theinsulating plates G are located. The insulating plates G are located asshown between the outer plates H and each extremity of the yoke. Twobolts H pass through each plate H, extremities G of connecting yoke Gand are secured in each broadened end F of the blades so that the bladesD, yoke G, outer plates H and insulating plates G2 are held firmlytogether so as to move as one and Serial No. 489,658. (No model.)

Heretofore the connecting yoke of two or 1 more blades was secured toeach blade by a single bolt and where. one. blade offered greaterresistance than the other in moving downward to complete the circuit theloose blade would start ahead and throw the two blades out of alignment,as the connecting yoke would turn on the bolt of the blade which oderedresistance to moving, as a pivot, and one blade would complete thecircuit on one side of the switch board before the other blade, and theentire current would pass through one side of the switch board, whichwould thereby be soon burned out. It will be seen by my improvement thatthe two bolts at each'end of the yoke prevent said connecting yoke fromturning on the end of one blade as a pivot, and the two blades cannot bethrown out of alignmentwith one another but must move as one andenterthe contact pieces simultaneously.

The usual construction of contact pieces consists in securing to thebase thereof thin copper pieces which are made flexible in order toyield as the blade of the switch enters between the same to complete thecircuit, but as it very often happens that the blade is not carried downto the full limit of the stroke the entire current would pass throughthe copper contactpieces, and not partly through the base, sothat astrong current would soon burn up these copper con-tact pieces. Now itis my intention to increase the carrying capacity of the contact piecesby securing on the outside of the copper contact pieces reinforcingplates by which the carrying capac- I do not limit myself to the exactarrangements and constructions shown as the same may be varied withoutdeparting from the spirit of my invention.

Having thus ascertained the nature and set forth the construction of myinvention, What I claim as new, and desire to secure by Letters Patentof the United States, is

1. In an electric switch, the combination with the contact pieces, ofblades pivoted at one end and having their free ends broadened, saidblades adapted to connect with said contact pieces to close the electriccircuit, and a connecting yoke for joining said blades together, havingits ends broadened to match the broadened ends of the blades, andsecured at each end to said blades by two bolts, whereby movement of oneupon the other is prevented.

2. In an electric switch, the .combination with the contact pieces, ofblades adapted to connect therewith to close the electric circuit, saidcontact pieces having flexible plates between which the blades pass toclose theelectric circuit, and rigid reinforcing plates scoured theretoto increase the carrying capacity of the said contact pieces.

3. In an electric switch, the combination with the contact pieces curvedinwardly at their upper ends, of blades contacting therewith to closethe circuit, said contact pieces having flexible plates between whichthe blades pass to close the circuit, and rigid reinforcing platessecured thereto to increase

